Static mixer crystallizer

Abstract

A static mixer crystallizer device includes at least one side wall defining a channel extending from a first end to a second end along a longitudinal axis. The channel receives a flow of a solution from the first end of the channel and expels the solution from the second end of the channel. The solution is a supersaturated solution comprising a fluid and dissolved salts. The device include a first structure disposed within the channel, the first structure comprising at least one surface comprising at least one of a reentrant surface, a crenellation, a concavity, or a corrugation configured to affect the flow of the solution through the channel to increase the turbidity thereof and accelerate a rate of crystal growth within the solution. The solution exiting the second end of the channel comprises salt crystals precipitated from the supersaturated solution.

Description

Attorney Docket No. 11255-036WO1STATIC MIXER CRYSTALLIZERCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 691,418, filed September 6, 2024, the entire contents of which are incorporated herein by reference.GOVERNMENT SUPPORT CLAUSE

[0002] This invention was made with government support under grant nos. R19AC00097, R20AC00006, and R23AC00437 awarded by the Bureau of Reclamation. The government has certain rights in the invention.BACKGROUND

[0003] Water recovery systems are designed to reclaim water from various sources (e.g., wastewater from residential or industrial processes), purify the water, and provide reusable water back to users. Such water recovery systems may be used in environments where water is scarce (e.g., drought periods, arid regions, or oceanic regions). Water recovery systems often implement reverse osmosis wherein water is forced through a semipermeable membrane, separating water from the dissolved salts and other impurities therein.

[0004] The byproducts of the filtration process, including reverse osmosis processes, include supersaturated solutions (e.g., having concentrations of salt deposits therein). To remove these potentially depositing salts from the solution, existing systems rely on crystallization devices and methods, which may include slow and expensive batch processes with simple stirring structures (e.g., paddles).

[0005] Therefore, a need exists for more efficient crystallization in water recovery systems.SUMMARY

[0006] One implementation of the present disclosure is a static mixer crystallizer device as described herein.

[0007] According to one implementation, a static mixer crystallizer device is disclosed. The device includes at least one side wall defining a channel extending from a first end to a second end spaced apart from the first end along a longitudinal axis. The channel is configured to receive a flow of a solution from the first end of the channel and expel the solution from the second end of the channel. The solution is a supersaturated solution including a fluid andAttorney Docket No. 11255-036WO1 dissolved salts. The device further includes a first structure disposed within the channel. The first structure includes at least one surface including at least one of a reentrant surface, a crenellation, a concavity, or a corrugation configured to affect the flow of the solution through the channel to increase the turbidity thereof and accelerate a rate of crystal growth within the solution. The solution exiting the second end of the channel includes salt crystals precipitated from the supersaturated solution.

[0008] In some implementations, the first structure is centrally disposed within the channel and is configured to urge the flow of the solution in a direction substantially perpendicular to the longitudinal axis and towards the at least one side wall.

[0009] In some implementations, the first structure is disposed adjacent to the at least one side wall and is configured to urge the flow of the solution in a direction substantially perpendicular to and towards the longitudinal axis of the channel.

[0010] In some implementations, the static mixer crystallizer device further includes a second structure disposed within the channel, the second structure including at least one surface including at least one of a reentrant surface, a crenellation, a concavity, or a corrugation configured to affect the flow of the solution through the channel to increase the turbidity thereof and accelerate the rate of crystal growth within the solution.

[0011] In some implementations, the second structure is coupled to the first structure. In some implementations, the second structure is angled relative to the first structure with respect to the longitudinal axis.

[0012] In some implementations, the first structure extends from a first side of the at least one side wall in a direction substantially parallel to the longitudinal axis and towards the second end of the channel. The first structure further curves radially inwardly towards the longitudinal axis such that an end of the first structure extends substantially perpendicular to the first side. The first structure is configured to urge the solution away from the first side of the at least one side wall and towards the longitudinal axis.

[0013] In some implementations, the static mixer crystallizer device further includes a second structure extending from a second side of the at least one side wall opposite from the first side and towards the longitudinal axis. The second structure further curves towards the first end of the channel. The second structure is configured to urge the solution towards the second side of the at least one side wall and away from the longitudinal axis, producing at least one chaotically mixed portion of the solution.Attorney Docket No. 11255-036WO1

[0014] Ln some implementations, the static mixer crystallizer device further includes a third structure extending from the first side of the at least one side wall in a direction substantially parallel to the at least one side wall and towards the second end of the channel. The third structure further curves radially inwards towards the longitudinal axis. The third structure further curves back towards the first end of the channel, forming a cavity facing toward the first end of the channel, the cavity configured to produce at least one chaotically mixed portion of the solution.

[0015] In some implementations, the static mixer crystallizer device further includes a fourth structure extending from the second side of the at least one side wall in a direction substantially parallel to the at least one side wall and towards the first end of the channel. The fourth structure further curves radially inwards towards the longitudinal axis. The fourth structure further curves back towards the second end of the channel, forming a cavity facing the second end of the channel, the cavity configured to urge a first portion of the solution towards the second side of the at least one side wall and a second portion of the solution towards the longitudinal axis of the channel.

[0016] In some implementations, the static mixer crystallizer device further includes a fifth structure disposed in a center of the channel substantially coaxial with the longitudinal axis. The fifth structure defines a cavity facing towards the second end of the channel such that the fifth structure urges a first portion of the solution towards the first side of the at least one side wall and a second portion of the solution towards the second side of the at least one side wall.

[0017] In some implementations, the static mixer crystallizer device further includes a sixth structure disposed in the center of the channel substantially coaxial with the longitudinal axis. The sixth structure defines a cavity facing towards the first end of the channel such that the sixth structure produces at least one chaotically mixed portion of the solution.

[0018] In some implementations, wherein the first structure is a spiral shape, a farfalle pasta shape, or a shell pasta shape. In some implementations, the first structure includes a thermoplastic material configured to be formed by additive manufacturing.

[0019] According to another implementation, a system for water treatment is disclosed. The system includes a first water treatment device, a static mixer crystallizer device, and a settling tank. The first water treatment device receives a solution from a first fluid inlet, wherein the solution is a supersaturated solution including a fluid and dissolved salts. The first water treatment device is configured to filter the solution and (i) expel a filtered solution along a first permeate conduit and (ii) expel a concentrated solution along a first reject conduit. The staticAttorney Docket No. 11255-036WO1 mixer crystallizer device is in fluid communication with the first reject conduit. The static mixer crystallizer device includes at least one side wall defining a channel extending from a first end to a second end spaced apart from the first end along a longitudinal axis. The channel is configured to receive a flow of the concentrated solution from the first reject conduit at a first end of the channel and expel the solution from the second end of the channel. A first structure of the static mixer crystallizer device is disposed within the channel. The first structure includes at least one surface including at least one of a reentrant surface, a crenellation, a concavity, or a corrugation configured to affect the flow of the concentrated solution through the channel to increase the turbidity thereof and accelerate a rate of crystal growth within the concentrated solution. The solution exiting the second end of the channel includes salt crystals precipitated from the supersaturated solution. The settling tank is in fluid communication with the second end of the channel of the static mixer crystallizer device. The settling tank includes one or more separation devices configured to separate the salt crystals from a liquid portion of the solution.

[0020] In some implementations, the first structure of the static mixer crystallizer device is centrally disposed within the channel and is configured to urge the flow of the solution in a direction substantially perpendicular to the longitudinal axis and towards the at least one side wall.

[0021] In some implementations, the first water treatment device is a first reverse osmosis device including a semi-permeable membrane.

[0022] In some implementations, the system further includes a second water treatment device in fluid communication with the first water treatment device. The first reject conduit of the first water treatment device feeds into the second water treatment device. The second water treatment device is configured to filter the solution and (i) expel a filtered solution along a second permeate conduit to the first permeate conduit and (ii) expel a further concentrated solution along a second reject conduit. The second reject conduit is coupled to and in fluid communication with the first end of the static mixer crystallizer device.

[0023] In some implementations, the second water treatment device is a first reverse osmosis device including a semi-permeable membrane.

[0024] In some implementations, the settling tank includes a crystal sludge conduit configured to receive and remove the salt crystals from the system. The settling tank further includes a third reject conduit configured to receive the liquid portion of the solution and urge them along the third reject conduit, which is coupled to the first reject conduit for reintroduction into the second water treatment device.Attorney Docket No. 11255-036WO1

[0025] The devices, systems, and methods are explained in even greater detail in the following drawings. The drawings are merely exemplary and certain features may be used singularly or in combination with other features. The drawings are not necessarily drawn to scale.

[0026] Additional advantages will be set forth in part in the description that follows or may be learned by practice. The advantages will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive, as claimed.BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 shows a diagram of a system for water treatment (e.g., a desalination system), according to one implementation.

[0028] FIG. 2 shows a cross-sectional view of an example static mixer crystallizer device, according to one implementation.

[0029] FIG. 3 shows a static mixer crystallizer device, according to one implementation.

[0030] FIG. 4 shows an image including 3D printed prototype internal structures configured to be disposed in the channel of a static mixer crystallizer, according to various implementations.

[0031] FIG. 5A shows an image including 3D printed prototype internal structures configured to be disposed in the channel of a static mixer crystallizer, according to various implementations.

[0032] FIG. 5B shows and image and corresponding models including 3D printed prototype internal structures configured to be disposed in the channel of a static mixer crystallizer, according to various implementations.

[0033] FIGS. 6A-6B show an experimental setup for a crystallizer device including a plurality of shell-pasta-shaped internal structures, according to one implementation.

[0034] FIG. 7A shows an experimental setup for a crystallizer device including a plurality of farfalle-pasta-shaped internal structures, according to one implementation.

[0035] FIG. 7B shows a diagram of an experimental setup for a crystallizer device implemented into a water treatment facility, according to one implementation.

[0036] Various objects, aspects, features, and advantages of the disclosure will become more apparent and better understood by referring to the detailed description taken in conjunction with the accompanying drawings, in which like reference characters identify corresponding elementsAttorney Docket No. 11255-036WO1 throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and / or structurally similar elements.DETAILED DESCRIPTION

[0037] Referring generally to the figures, a static mixer crystallizer is shown, according to various implementations.

[0038] Disclosed herein are devices, systems, and methods for the design and use of an improved static mixer to accelerate crystal growth from a supersaturated solution. An example application of the disclosed static mixer is the handling and processing of the supersaturated aqueous solutions produced during the desalination of inland water. One overarching advantage is lowering the volume and cost of the concentrated reject produced from reverse osmosis desalination. The disclosed mechanism induces the crystallization of supersaturated solutions (e.g., targeting typical reverse osmosis (RO) concentrate) at a faster rate than existing devices and systems.

[0039] The disclosed mechanism can drop out precipitants within and after the mixer, increasing overall recovery by further treating the solution that is partially “softened”. The disclosed systems, methods, and devices may include the use of a base if the supersaturated solution contains anti-scalants. In other implementations, no additional chemicals or heat are added. The disclosed mechanism inputs energy into the solution, providing a driving force behind the increased crystallization rate. In some examples, the disclosed systems, methods, and devices provide novel shapes and / or materials for internal components of the static mixer. In some implementations, the internal components of the static mixer are 3D printed with a complex geometry. In some implementations, components of the static mixer crystallizer (e.g., the internal components and / or a sidewall) include a plastic material (e.g., polymer materials). In other implementations, the components of the static mixer crystallizer include materials having a coefficient of friction and / or a surface chemical potential configured to provide sufficient surface collisions and / or flow rate of the solution to produce enhanced crystallization.

[0040] In some implementations, the internal components of the static mixer may include a surface area to volume ratio that is controlled or calibrated based on the overall size of the mixer, the flow rate of solution therethrough, the level of supersaturation of the solution, a desired level of turbidity, and / or other flow properties relevant to the crystallization process. Some examples of static mixer crystallizers are designed with specific values or ranges of residence times, fluid velocity, and / or energy dissipation per unit length, depending on the specific operating conditions.Attorney Docket No. 11255-036WO1

[0041] Ln some implementations, the internal components of the static mixer include complex topologies and / or geometries that initiate higher turbidity. For example, the topologies may include reentrant structures or structures that double-back or curl in on themselves (e.g., crenellations, wrinkles, spirals, pleats, corrugations, creases, pleats, ridges, openings, gaps, slots, and / or other irregular or regular patterns in the topology). For example, a reentrant surface structure may be defined as a concave topographic curvature that exists from the top to the bottom of a structure. Such reentrant surfaces and structures have been designed in various shapes ranging from mushroom, overhang, trapezoid, undercut, spatula, taper, and sphere to sharp edge.

[0042] The topologies and reentrant surfaces therein may be configured to force a flow of the solution in a direction away from the longitudinal flow direction, such as perpendicular to a side wall or substantially perpendicular to the longitudinal flow direction. In some examples, the topologies include one or more asymmetric portions with respect to a principal axis (e.g., one or more of the longitudinal axis or a perpendicular transverse axis). In some examples, the topologies include angular rotation portions configured to produce a swirl or an angular rotation of the solution along the longitudinal or transverse axes.Example System

[0043] FIG. 1 shows a system 10 for water treatment (e.g., a desalination system). The system 10 is a multi-stage reverse osmosis system including a first reverse osmosis (RO) system 12 and a second reverse osmosis (RO) system 14 in fluid communication with each other (e.g., via one or more conduits or pipes). The first RO system 12 may be a conventional reverse osmosis stage including one or more modules containing a semi-permeable membrane. Feedwater from the input line 16 enters the first RO system 12 to be filtered by the semi-permeable membrane. The pores of the semi-permeable membrane allow water to pass through but block larger molecules (e.g., bacteria, salts, and other contaminants). Water that passes through the membrane of the first RO system 12 (e.g., the permeate) continues along the permeate line 18 as relatively pure water. The concentrate rejected from the first RO system 12 (e.g., saturated solution) proceeds along the reject line 20 for further treatment.

[0044] The second RO system 14 receives saturated or supersaturated solution from the reject line 20 for processing. The second RO system 14 may be a high recovery reverse osmosis system, a closed circuit reverse osmosis system, or a similar system. Similar to the first RO system 12, the second RO system 14 filters the supersaturated solution (e.g., via a semipermeable membrane), sending the permeate to the permeate line 18 and sending theAttorney Docket No. 11255-036WO1 rejected supersaturated solution along the second reject line 22 (e.g., along one or more pipes or conduits).

[0045] The second reject line 22 feeds the supersaturated solution to a continuous crystallizer device 24 (e.g., a device as disclosed herein). The continuous crystallizer device 24 handles the dissolved salts in the supersaturated solution. For example, as the dissolved salts reach their solubility limit, the continuous crystallizer device 24 facilitates crystallization and allows the salts to precipitate out as solid crystals. The result is a higher overall recovery rate of water due to the removal of the salts.

[0046] A settling tank 26 is shown adjacent to and in fluid communication with the continuous crystallizer device 24. The settling tank 26 provides liquid / solid separation of the mixture following the precipitation in the continuous crystallizer device 24. The settling tank 26 may include devices to facilitate this separation (e.g., centrifuge or other device). Once separated, a crystal sludge is removed via the crystal sludge line 28. The precipitated salts of the crystal sludge may be recovered and repurposed for other uses. The solution remaining after the settling process is sent back to the second RO system 14 along the recovery line 30 for additional processing.Example Crystallizer Devices

[0047] FIG. 2 shows an example static mixer crystallizer device 100 (e.g., used as the continuous crystallizer device 24 in the system 10 of FIG. 1). The crystallizer device 100 of FIG. 1 is a cross-section of a cylindrical crystallizer device along one longitudinal plane. The crystallizer device 100 is an example template showcasing some examples of the inner structures and interactions of the crystallizer devices disclosed herein. The crystallizer device 100 includes a variety of structures, any of which may be reorganized, repeated, replaced, reversed, or otherwise modified and / or combined in as many combinations or permutations as is practical. Additionally, while a cross-section along one plane is shown, any of the internal structures may be disposed or may extend between different portions of the sidewall or internal channel such that a different cross-section along a different longitudinal plane would reveal a differently shaped structure (e.g., a combination of two structures as shown).

[0048] The crystallizer device 100 includes at least one side wall 102 defining a channel 104. The at least one side wall 102 is cylindrical, forming a cylindrical channel 104. However, in other implementations, the at least one side wall may include more than one wall and / or may define a differently shaped channel (e.g., having an elliptical, square, rectangular, or hexagonal cross-sectional shape). A longitudinal axis 106 extends through a center of the channel 104 to beAttorney Docket No. 11255-036WO1 coaxial with the channel 104 and equidistance from all portions of the at least one side wall 102. For example, the longitudinal axis 106 is spaced apart from a first side 102a of the at least one side wall 102 the same distance as the longitudinal axis 106 is spaced apart from a second side 102b of the at least one side wall 102. The crystallizer device 100 shown in FIG. 2 is a linear crystallizer device 100 wherein the channel 104 and the longitudinal axis 106 are linear. However, in other implementations, the crystallizer device may take a different shape (e.g., arcuate, curved, or otherwise non-linear along its length).

[0049] The crystallizer device 100 is configured to provide a flow of supersaturated solution through the device from a first end 108 to a second end 110 spaced apart from the first end 108 along the longitudinal axis 106. A supersaturated concentrate enters the first end 108 of the crystallizer device 100, and a de-supersaturated water with crystal slurry (e.g., a mixture of water and precipitated salt crystals) exits the second end 110 of the crystallizer device 100.

[0050] To initiate the crystallization of the salts, the crystallizer device 100 includes internal structures that affect the flow path, increase the overall chaotic mixing and / or pressure differential in the flow path, and increase the number of nucleation sites for crystallization. Chaotic mixing or chaotic advection refers to the phenomenon where fluid particles exhibit sensitive dependence on initial conditions, meaning that even tiny differences in starting points can lead to drastically different trajectories over time. Simple, low Reynolds number flow can lead to the onset of Lagrangian chaos. Even steady three-dimensional flows can exhibit chaotic advection and / or chaotic mixing.

[0051] The internal structures facilitate the precipitation of the salt crystals, increasing the overall turbidity of the solution flowing therethrough. In general, higher turbidity (NTU) correlates with higher nucleation of crystals. Throughout the following examples, “fluid” and “solution” may be used interchangeably to refer to the aqueous mixture of dissolved and / or undissolved salts or other additives that flows through the device.

[0052] Various examples of internal structures and their effect on the fluid flow path are shown in FIG. 2. For example, a first structure 112 is shown extending from the first side 102a in a direction substantially parallel to the longitudinal axis 106 towards the second end 110. Then, the first structure 112 curves radially inwardly towards the longitudinal axis 106 such that the end of the first structure 112 is substantially perpendicular to the first side 102a and the longitudinal axis 106. The first structure 112 affects the overall flow path of the solution by forcing the fluid / solution away from the first side 102a and toward the center of the channel 104 in a direction substantially perpendicular to the longitudinal axis 106.Attorney Docket No. 11255-036WO1

[0053] A second structure 114 is shown extending from the second side 102b radially inwardly in a direction substantially perpendicular to the second side 102b. The second structure 1 14 then curves “backward” towards the first end 108 of the channel 104 in a direction opposite the fluid flow direction. The end of the second structure 114 is substantially parallel to the longitudinal axis 106. The second structure 114 affects the overall flow path of the solution by forcing the fluid / solution towards the second side 102b of the at least one side wall 102, causing a turbulent cavity wherein the fluid / solution doubles back on itself.

[0054] A third structure 116 is shown extending from the first side 102a in a direction towards the second end 110 and substantially parallel to the first side 102a and the longitudinal axis 106. The third structure 116 then curves radially inwardly to be substantially perpendicular to the longitudinal axis 106, and then the third structure 116 continues curving back towards the first end 108 to be substantially parallel to the longitudinal axis 106 again. Thus, the third structure 116 forms a U-shape or parabolic shape with an open end facing the first end 108 from which the fluid flows. The third structure 116 forms and defines a cavity adjacent to the first side 102a. The third structure 116 affects the overall flow path of the solution by forcing the fluid adjacent the first side 102a backward towards the first end 108 and inwards towards the longitudinal axis 106. The third structure 116 may create a turbulent cavity or portion in the fluid flow path wherein the fluid doubles back on itself.

[0055] A fourth structure 118 is shown extending from the second side 102b in a direction towards the first end 108 and substantially parallel to the second side 102b and the longitudinal axis 106. The fourth structure 118 then curves radially inwardly to be substantially perpendicular to the longitudinal axis 106, and then the fourth structure 118 continues curving back towards the second end 110 to be substantially parallel to the longitudinal axis 106 again. Thus, the fourth structure 118 forms a U-shape or parabolic shape with an open end facing the second end 110 towards which the fluid flows. The fourth structure 118 forms a cavity adjacent the second side 102b (e.g., a cavity opposite-facing compared to the third structure 116). The fourth structure 118 affects the overall flow path of the solution by splitting a portion of the fluid - forcing a portion towards the second side 102b and another portion towards the longitudinal axis 106.

[0056] A fifth structure 120 is shown disposed in the center of the channel 104 coaxial with the longitudinal axis 106. The fifth structure 120 may be coupled to a portion of the at least one side wall 102 along a portion not shown by the cross-sectional view of FIG. 2. Alternatively or additionally, the fifth structure 120 may be coupled centrally to a different one of the internal structures (e.g., along a longitudinal base structure extending a length of the channel 104). The fifth structure 120 affects the overall flow path of the solution by splitting a portion of the fluidAttorney Docket No. 11255-036WO1 towards the first side 102a and another portion of the fluid towards the second side 102b. In some implementations, the fifth structure may force one or more portions of the fluid substantially perpendicularly with respect to the longitudinal axis 106 and the longitudinal flow path.

[0057] A sixth structure 122 is shown disposed in the center of the channel 104 coaxial with the longitudinal axis 106 in a similar manner to that of the fifth structure 120. The sixth structure 122 forms a cavity such that fluid flowing in a central portion of the channel 104 is caught in the cavity and swirled around or directed substantially backward. The sixth structure 122 and the turbulent cavity formed therein further force fluid around the sixth structure 122 toward each of the first side 102a and the second side 102b.

[0058] A seventh structure 124 is a combination of the fifth structure 120 and versions of the first structure 112 or the third structure 116. For example, the seventh structure 124 includes a first portion disposed in the center of the channel 104 (e.g., similar to the fifth structure 120), a second portion extending from the first side 102a (e.g., similar to the third structure 1 16), a third portion extending from the second side 102b (e.g., similar to a mirrored version of the third structure 116). In other words, the first, central portion of the seventh structure 124 guides the flow of fluid towards each of the first side 102a and the second side 102b of the at least one side wall 102, and the wall-adjacent portions of the seventh structure 124 guide the flow of fluid back towards the longitudinal axis 106. A cavity 125 is formed where the fluid doubles back on itself within the first portion of the seventh structure 124. A channel is defined between the wall- adjacent portions of the seventh structure 124 through which fluid flows away from the cavity 125.

[0059] It is understood that the cross-sectional view in FIG. 2 is a representation of the overall internal structures. Therefore, each of the first, central portion and the wall-adjacent portions of the seventh structure 124 may be a single, contiguous structure.

[0060] Each of the first structure 1 12, the second structure 114, the third structure 116, the fourth structure 118, the fifth structure 120, the sixth structure 122, and the seventh structure 124 may be combined with each other, modified to conform to each other, or otherwise formed adjacent to each other in a variety of combinations and permutations. Each one of the structures shown and described in FIG. 2 (and any combinations thereof) facilitates the precipitation of salts from the solution flowing through. For example, the internal structures increase the chaotic mixing, pressure-differential, and nucleation sites for the salt to crystalize.Example Internal Structures and UsageAttorney Docket No. 11255-036WO1

[0061] FIG. 3 shows a static mixer crystallizer device 200, according to one example. The crystallizer device 200 includes a side wall 202 defining a cylindrical channel 204 within which fluid (e.g., supersaturated fluid) flows. The flow path through the channel 204 extends from the first end 208 to a second end 210 spaced apart from the first end 208 along a longitudinal axis 206.

[0062] The static mixer crystallizer device 200 includes several internal structures (e.g., similar to the structures in the cross-sectional view of the crystallizer device 100 of FIG. 2). Specifically, the static mixer crystallizer device 200 includes a first structure 212 that includes various surfaces that affect the flow path of fluid through the channel 204. For example, some of the surfaces of the first structure 212 force fluid toward the central longitudinal axis 206, while other surfaces of the first structure 212 force fluid away from the longitudinal axis 206. A pressure differential diagram is shown adjacent to the static mixer crystallizer device 200, which shows an example of the various flow paths induced by the internal structures. The internal structures include, for example, reentrant surfaces that force the fluid to double back on itself, increasing the overall chaotic mixing and the nucleation sites for the salts in the solution.

[0063] The first structure 212 is inspired and based on a farfalle pasta shape. FIGS. 4 and 5, showing additional shapes for the internal structures, show the same first structure 212 and the farfalle shape as a 3D printed prototype. The farfalle shape includes multiple reentrant surfaces and a combination of structures, surfaces, and edges that affect the flow of the fluid through the channel. However, the farfalle shape, and other shapes shown and described herein, are exemplary only, and variations and combinations thereof are contemplated by this disclosure.

[0064] The static mixer crystallizer device 200 includes a second structure 214, a third structure 216, and a fourth structure 218. The second structure 214, the third structure 216, and the fourth structure 218 are each the same shape as the farfalle pasta shape of the first structure 212. However, each of the second structure 214, the third structure 216, and the fourth structure 218 are angled about the longitudinal axis 206 with respect to each other (e.g., at a right angle or, in other implementations, any angle greater than 0 degrees). Each of the first structure 212, the second structure 214, the third structure 216, and the fourth structure 218 may be integrally formed with each other and / or coupled to one another to form a contiguous structure. The differently angled structures 212-218 may induce angular velocity about the longitudinal axis 206 into the flow path, further increasing the chaotic mixing of the flow and the precipitation of the salts therein.

[0065] FIG. 4 shows an image including the first structure 212 (e.g., the farfalle pasta shape) alongside other 3D printed prototype internal structures configured to be disposed in the channelAttorney Docket No. 11255-036WO1 of a static mixer crystallizer. For example, a first spiral 301, a second spiral 302, and a third spiral 303 are each shown in FIG. 4. Each of the first spiral 301 , the second spiral 302, and the third spiral 303 have a different length, width, and / or pitch. Each of the example structures shown in FIG. 4 may be modified, combined, and used in conjunction with another one of the structures described herein.

[0066] Similarly, FIG. 5A shows an image of 3D-printed prototypical internal structures for static mixer crystallizers. FIG. 5 A shows another implementation of the first structure (e.g., the farfalle shape) shown as structure 212a. Additionally, FIG. 5 A shows a shell pasta shape 310 configured to be disposed within a static mixer crystallizer. Compared to the farfalle shape, the shell pasta shape 310 - implemented as the internal structure for the static mixer crystallizer device - includes more reentrant surfaces, cavities, and asymmetries with respect to the longitudinal axis within which fluid may double-back and otherwise increase chaotic mixing and resulting turbidity.

[0067] Similarly, FIG. 5B shows models and 3D-printed prototypical internal structures for static mixer crystallizers. FIG. 5B shows another implementation of the farfalle shape and the shell shape. Additionally, FIG. 5B includes an hourglass shape and a rotelle pasta shape. The rotelle shape includes a plurality of channels in a pinwheel-type arrangement. Any of the internal structures of FIG. 5B, including the hourglass shape, the rotelle shape, or any individual features thereof, may be implemented into the static mixer crystallizer devices of the present disclosure.

[0068] Overall, the disclosed internal structures of the static mixer crystallizer devices (e.g., the first structure 212 as the farfalle pasta shape, the shell pasta shape 310, the spirals 301, 302, 303, or any variations or combinations thereof) increase the turbidity of the fluid flowing through the device. The increased turbidity provided by the disclosed device is advantageous at least because it facilitates crystallization and allows salts in the solution to precipitate out as solid crystals. The result is a higher overall recovery rate of water in a system due to the removal of the salts.

[0069] Additionally or alternatively, the disclosed internal structures of the static mixer crystallizer devices (e.g., the first structure 212 as the farfalle pasta shape, the shell pasta shape 310, the spirals 301, 302, 303, or any variations or combinations thereof) provide manufacturing advantages over existing mixer devices. In some examples, the disclosed internal structures are 3D printed or otherwise produced via additive manufacturing. In other implementations, the disclosed internal structures may be produced through a molding process. By contrast, existing mixer devices often include simple structures produced in an extrusion process with a static die, which limits the shape variations. Furthermore, the disclosed internal structures may be producedAttorney Docket No. 11255-036WO1 more quickly with reduced costs, particularly for the additive manufacturing processes (e.g., 3D printing).

[0070] In some examples, the disclosed internal structures include a plastic material capable of additive manufacturing. For example, the disclosed internal structures include polymers such as nylon 6, ethylene vinyl alcohol (EVOH), polyethylene terephthalate glycol (PETG), acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), or other thermoplastic polymers. The polymers used for the internal structures provide surface characteristics that are advantageous for facilitating crystallization and salt precipitation. For example, the polymers may be in whole or in part hydrophilic. In some examples, the polymers have a surface characterized by a heterogeneous pattern of hydrophilic and / or hydrophobic portions (e.g., at the molecular level). In some examples, the heterogeneity of the surface of the internal structures provides enhanced crystallization and salt precipitation by reducing the instances of crystals sticking to the surface and / or increasing a localized flow rate.Experimental Study and Results

[0071] A study was conducted wherein a series of shell pasta shape 310 internal structures were coupled together longitudinally and installed within a tube 312, as shown in FIGS. 6 A and 6B. FIG. 6A shows a first end of the tube 312 with the plurality of internal structures (e.g., the shell pasta shape 310) disposed therein. FIG. 6B shows another portion of the same tube 312 with the shell pasta shape 310 internal structures. FIGS. 6A and 6B also show fluid flowing through the channel having a cloudy appearance - indicating precipitated salts.

[0072] Table 1 below shows the results of the study wherein four different trials were conducted. The tube of the study (e.g., the tube 312) included a nominal diameter of 2.5 cm and a length of 120 cm. The study varied the overall flow rate (Q, mL / s) through the tube (corresponding to a varied entrance velocity (cm / s)), and it measured the average pressure difference (AP avg, psi), residence time of the solution within the tube volume (r, min.), mass deposited (g / L), and the overall turbidity (NTU) of the solution.

[0073] Another study was conducted in a lab setting using two pipes with static mixer crystallizer devices coupled in series, as shown in FIG. 7A. The laboratory setup included fluidAttorney Docket No. 11255-036WO1 recirculation directly from the end of one pipe to the input of the other pipe. The precipitated solids increased over time wherein a residence time of 1.7 minutes was observed for one trial. Overall, the laboratory setup of FIG. 7A verified the performance of the static mixer crystallizer device with internal structures therein (e.g., the farfalle pasta shape structures).

[0074] Another study was conducted wherein a static mixer crystallizer device was installed in-situ at a water treatment facility. The study verified the use of the static mixer crystallizer device in a real-world application with the variations in fluid flow and composition that occurs in real scenarios. As shown in FIG. 7B, the static mixer crystallizer device received the aqueous solution from a reverse osmosis concentrate source. The facility also added an antiscalant to the solution, thus requiring a periodic small dosage of NaOH. The static mixer crystallizer device was a 2.5 cm diameter pipe with internal structures therein (e.g., the farfalle pasta shape structures). At the exit of the static mixer crystallizer device, the de-supersaturated water with crystal slurry was collected and the solid crystals collected. In one trial, the static mixer crystallizer device induced calcite (CaCO3) solid formation at a concentration of 1677.5 mg / L. In another trial, the static mixer crystallizer device induced lechatelierite (SiO2) formation at a concentration of 79.8 mg / L. Overall, the in-field study verified the advantages of the disclosed device.Configuration of Certain Implementations

[0075] The construction and arrangement of the systems and methods as shown in the various implementations are illustrative only. Although only a few implementations have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes, and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.). For example, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative implementations. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the implementations without departing from the scope of the present disclosure.

[0076] Although the figures show a specific order of method steps, the order of the steps may differ from what is depicted. Also, two or more steps may be performed concurrently or with partial concurrence. Such variation will depend on the software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations could be accomplished with standard programming techniques withAttorney Docket No. 11255-036WO1 rule-based logic and other logic to accomplish the various connection steps, processing steps, comparison steps and decision steps.

[0077] It is to be understood that the methods and systems are not limited to specific synthetic methods, specific components, or to particular compositions. It is also to be understood that the terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting.

[0078] As used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” one particular value, and / or to “about” another particular value. When such a range is expressed, another implementation includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another implementation. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

[0079] “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not. Throughout the description and claims of this specification, the word “comprise” and variations of the word, such as “comprising” and “comprises,” means “including but not limited to,” and is not intended to exclude, for example, other additives, components, integers or steps. “Exemplary” means “an example of” and is not intended to convey an indication of a preferred or ideal implementation. “Such as” is not used in a restrictive sense, but for explanatory purposes.

[0080] Disclosed are components that can be used to perform the disclosed methods and systems. These and other components are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these components are disclosed that while specific reference of each various individual and collective combinations and permutation of these may not be explicitly disclosed, each is specifically contemplated and described herein, for all methods and systems. This applies to all aspects of this application including, but not limited to, steps in disclosed methods. Thus, if there are a variety of additional steps that can be performed it is understood that each of these additional steps can be performed with any specific implementation or combination of implementations of the disclosed methods.

Claims

Attorney Docket No. 11255-036WO1WHAT IS CLAIMED IS:

1. A static mixer crystallizer device comprising: at least one side wall defining a channel extending from a first end to a second end spaced apart from the first end along a longitudinal axis, wherein the channel is configured to receive a flow of a solution from the first end of the channel and expel the solution from the second end of the channel, wherein the solution is a supersaturated solution comprising a fluid and dissolved salts; and a first structure disposed within the channel, the first structure comprising at least one surface comprising at least one of a reentrant surface, a crenellation, a concavity, or a corrugation configured to affect the flow of the solution through the channel to increase the turbidity thereof and accelerate a rate of crystal growth within the solution, wherein the solution exiting the second end of the channel comprises salt crystals precipitated from the supersaturated solution.

2. The static mixer crystallizer device of claim 1, wherein the first structure is centrally disposed within the channel and is configured to urge the flow of the solution in a direction substantially perpendicular to the longitudinal axis and towards the at least one side wall.

3. The static mixer crystallizer device of any of claims 1-2, wherein the first structure is disposed adjacent to the at least one side wall and is configured to urge the flow of the solution in a direction substantially perpendicular to and towards the longitudinal axis of the channel.

4. The static mixer crystallizer device of any of claims 1-3, further comprising a second structure disposed within the channel, the second structure comprising at least one surface comprising at least one of a reentrant surface, a crenellation, a concavity, or a corrugation configured to affect the flow of the solution through the channel to increase the turbidity thereof and accelerate the rate of crystal growth within the solution.

5. The static mixer crystallizer device of claim 4, wherein the second structure is coupled to the first structure.Attorney Docket No. 11255-036WO16. The static mixer crystallizer device of claims 4 or 5, wherein the second structure is angled relative to the first structure with respect to the longitudinal axis.

7. The static mixer crystallizer device of any of claims 1-6, wherein the first structure extends from a first side of the at least one side wall in a direction substantially parallel to the longitudinal axis and towards the second end of the channel, the first structure further curving radially inwardly towards the longitudinal axis such that an end of the first structure extends substantially perpendicular’ to the first side, wherein the first structure is configured to urge the solution away from the first side of the at least one side wall and towards the longitudinal axis.

8. The static mixer crystallizer device of any of claims 1-7, further comprising a second structure extending from a second side of the at least one side wall opposite from the first side and towards the longitudinal axis, the second structure further curving towards the first end of the channel, wherein the second structure is configured to urge the solution towards the second side of the at least one side wall and away from the longitudinal axis, producing at least one chaotically mixed portion of the solution.

9. The static mixer crystallizer device of any of claims 1-8, further comprising a third structure extending from the first side of the at least one side wall in a direction substantially parallel to the at least one side wall and towards the second end of the channel, the third structure further curving radially inwards towards the longitudinal axis, the third structure further curving back towards the first end of the channel, forming a cavity facing toward the first end of the channel, the cavity configured to produce at least one chaotically mixed portion of the solution.

10. The static mixer crystallizer device of any of claims 1-9, further comprising a fourth structure extending from the second side of the at least one side wall in a direction substantially parallel to the at least one side wall and towards the first end of the channel, the fourth structure further curving radially inwards towards the longitudinal axis, the fourth structure further curving back towards the second end of the channel, forming a cavity facing the second end of the channel, the cavity configured to urge a first portion of the solution towards the second sideAttorney Docket No. 11255-036WO1 of the at least one side wall and a second portion of the solution towards the longitudinal axis of the channel.

11. The static mixer crystallizer device of any of claims 1-10, further comprising a fifth structure disposed in a center of the channel substantially coaxial with the longitudinal axis, wherein the fifth structure defines a cavity facing towards the second end of the channel such that the fifth structure urges a first portion of the solution towards the first side of the at least one side wall and a second portion of the solution towards the second side of the at least one side wall.

12. The static mixer crystallizer device of any of claims 1-11, further comprising a sixth structure disposed in the center of the channel substantially coaxial with the longitudinal axis, wherein the sixth structure defines a cavity facing towards the first end of the channel such that the sixth structure produces at least one chaotically mixed portion of the solution.

13. The static mixer crystallizer device of any of claims 1-12, wherein the first structure is a spiral shape, a farfalle pasta shape, a shell pasta shape, or a rotelie pasta shape.

14. The static mixer crystallizer device of any of claims 1-13, wherein the first structure comprises a thermoplastic material configured to be formed by additive manufacturing.

15. A system for water treatment, comprising: a first water treatment device receiving a solution from a first fluid inlet, wherein the solution is a supersaturated solution comprising a fluid and dissolved salts, wherein the first water treatment device configured to filter the solution and (i) expel a filtered solution along a first permeate conduit and (ii) expel a concentrated solution along a first reject conduit; a static mixer crystallizer device in fluid communication with the first reject conduit, the static mixer crystallizer device comprising:Attorney Docket No. 11255-036WO1 at least one side wall defining a channel extending from a first end to a second end spaced apart from the first end along a longitudinal axis, wherein the channel is configured to receive a flow of the concentrated solution from the first reject conduit at a first end of the channel and expel the solution from the second end of the channel; and a first structure disposed within the channel, the first structure comprising at least one surface comprising at least one of a reentrant surface, a crenellation, a concavity, or a corrugation configured to affect the flow of the concentrated solution through the channel to increase the turbidity thereof and accelerate a rate of crystal growth within the concentrated solution, wherein the solution exiting the second end of the channel comprises salt crystals precipitated from the supersaturated solution; and a settling tank in fluid communication with the second end of the channel of the static mixer crystallizer device, the settling tank comprising one or more separation devices configured to separate the salt crystals from a liquid portion of the solution.

16. The system of claim 15, wherein the first structure of the static mixer crystallizer device is centrally disposed within the channel and is configured to urge the flow of the solution in a direction substantially perpendicular to the longitudinal axis and towards the at least one side wall.

17. The system of any of claims 15-16, wherein the first water treatment device is a first reverse osmosis device comprising one or more modules with a semi-permeable membrane.

18. The system of any of claims 15-17, further comprising a second water treatment device in fluid communication with the first water treatment device, wherein the first reject conduit of the first water treatment device feeds into the second water treatment device, wherein the second water treatment device configured to filter the solution and (i) expel a filtered solution along a second permeate conduit to the first permeate conduit and (ii) expel a further concentrated solution along a second reject conduit, wherein the second reject conduit is coupled to and in fluid communication with the first end of the static mixer crystallizer device.Attorney Docket No. 11255-036WO119. The system of any of claims 15-18, wherein the second water treatment device is a first reverse osmosis device comprising one or more modules with a scmi-pcrmcablc membrane.

20. The system of any of claims 15-19, wherein the settling tank comprises: a crystal sludge conduit configured to receive and remove the salt crystals from the system; and a third reject conduit configured to receive the liquid portion of the solution and urge them along the third reject conduit, which is coupled to the first reject conduit for reintroduction into the second water treatment device.

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